Baking-oven.



W. S. GORBY & J. L. PARSONS, Jn.

BAKING OVEN.

APPLIOATION FILED 00T. 12, 1912.

Patented Aug. 11, 1914.

3 SHEETS-SHEET 1.

WWA/? .vnf MN.

W. S. GORBY & J. LJPARSONS, JR. BAKING OVEN. APPLIOATION FILED 0612.12. 1912.

1,1 07,1 95. Patented Aug. 11, 1914.v a SHEETS-SHEET 2'.

W. S. CORBY- & J. L. PARSONS, Jn.

BAKING OVEN.

` APPLICATION FILED 00T. 12 1912.'.

Patented Aug. 11, 1914;

s SHEETS-emma.

UNITED STATES. (,)FFICE WILLIAM s. oonia'rv AND JAMES I.. PAnsoNs, Jn..,' or WASHINGTON, nIs'rRIcr v oF COLUMBIA.

' BAKING-OVEN.

Specification of Letters Patent.

Patented Aug/11, 1914.'.

Application filed October-12,' 15H2. 'SerialNm 725,514.

-To all whom 'it may concern Be it known that we, VILLIAM S. Conni* and 'JAMES L. PAnsoNs, Jr., citizens of the new form of oven are the doubling of the' baking capacity `for a given Hoor space as compared with the type of ovens 'new gen erall yin use, the adaptability for continuous operation twenty-four hours a day, and economy of fuel resulting from' the conservation and utilization of heat.

Some of the objects, therefore, of the in venticn are to provide an oven constructed to have the advantages mentioned.

Another' object is to provide an improved oven so constructed that the bread loaves or other articles being baked are fully protected from the gaseous products .of combustion. (Ether objects will be apparent from the Afollowing specification and claims.

' In the drawings which illustrate one embodiment oi' our invention Figure 1 is a 'front elevation of the oven, parts of the charging "l'loor being broken away. Fig. 2 is rear elevation. Fig.v 3 is a longitudinal vertical sectional view on the line 3 3' of Fig. 1l, parte being broken away. Fig. 4 is a transverse vertical sectional. view on the line ot Fig. 3. Fig. 5 isa horizontal sectional view on the line 5-5 of- Fig. 3. Fig. 6 shows in cross section the preferred 'form of tray bottom on a larger scale. Figs.

7 and S are a longitudinal section l'and a cross section cfa modied'form of tray bottom.

Referring to the drawings, the numerals 1, 1 indicate the thick vertical side walls lof the oven extending in unbroken lines fromV the first floor 2 up through' the second floor 3 and oined at their tops by a semi-circular arch L 'extending from the rear wall 5to the front wall 6. These valle inclose an.

explained.

and permanently closed against external communication except at the'4 extreme bottom, as will be hereinafter described.

7 is a baking container positioned inthe .upper portion of Ythe oven, its walls being separated at all points from' the'walls of the oven. Preferably the lcontainer 7 is quasicylindrical in form. VThe upper portion or half of this cylinder or drum is preferably approximately semi-circular cross section,- whereas the lower portlon is. flattened out to be approximately semi-elliptical in cross section for a purpose which will beA later A shaft 8 extends longitudinally through .the oven and end Walls of the drum 7. This lshaft is supported in suitable bearings 9v -drum 7. The arms 10 vot the spiders are braced or stitfened by bars or straps 12.

insulated heating chamber which is entirely' Shafts 1 3 extend parallel with'the main shaft 8 from the ends of the arms 10 of one spider to the 'ends of: the arms 10 of the opposite spider. -The swinging bread trays 14 are carried bythe sha't'ts '13. As it is desirable to have the bread trays travel 1n close,proximity to the inner surface of ythe drum 7, the lower halt` of this drum, as.

previously described, is ilattened out'to convform more closely to the lower half ofthe V travel of the swinging trays.'

At the' lowest point of the 7 opening 15 is vprovided in the frontwalls 6 of the oven. -Through this opening the bread orether material to be baked is shoved upon the long trays 14. A door, 16 closes theopening.

Secured on the front end of the 'shatS4 is a large worm wheelv 17 meshing with a worm 18 carried by one end ofthe vhorizon-44 tally arrangedshaft 19. .This shaft extends across the front face of the ovenand 'has secured to its opposite end a pulley 2 0. This may be driven rom anyl suitable source .of power. yA clutch 21 'is interposed between the 'shaft 19 and the pulley 20.. Theclutch operating lever 22 is the-.oven door 16 so t at' the baker'may readily stop the rotation ofA the reel when a.

4tray registers exactly with the oven" door.

ositioned, adjacent:

ioo

A large reduction in gearing is provided so that the drum may rotate at a comparatively slow speed. e

The lower portion of the ovenis provided, as is particularly well illustrated in F ig. 4,. with three longitudinal arched tunnels 25,

.2G-and 27. A transverse header 28 joins all three tunnels at the front end of the oven.

l' A grate 29 is positioned in the rearV of theV central tunnel 26, thus converting this cham,

, hen into" a heat 'generating furnace. The

*grate extends a comparatively short distancel longitudinally intolthe tunnel 26, the re maining portion being floored'over as at 30 at a height approximately equal to that ofv the grate bars. In the same manner the tunnels and 27 are flocred at the same level as the floor 30. Flues 31 extend from the tunnels 25 and 27 up into the large open space 3 2. Dampers 33 regulate the passage of gases through the flues 31, their position being regulated by shafts 34ext'end'ng out through'the rear face of the oven and pr .-vided with hand levers 35. Flues 36 extend from the rear ends of theltunnels 25 and 27 up through the rear Wall 5 of the oven `and are connected to a chimney. The passage of gases into the ues 36 is regulated by dampers 37. Thelues 36 communicate with a discharge duct 38. Thus, it will'be seen that the oven extends 4through two floors, the llrst floor being used for charging fuel into the furnace at the'ear of the.

oven, whereas the second floor is located at a level -where the rotating vtrays can be `charged with material to be baked.

As before stated, the ovenv isfadap'ted to operate day in and day out, twenty-four hours each day. To first start the oven in operation a fire is built on the grate 29, the dampers 33 being closed and the dampers 37 open. It will require approximately twenty-four hours to heat the oven to the proper baking point. A good bed of coals having been obtained, the dampers 37 are closed and the dampers 33 opened, the trays in the rotating reel being then charged with bread and the rotation of the reel started. As the chimney flues are now closed and the `iues connecting the arched. -tuniels 25 land 27 to the chamber 32 open, active combustion will cease and the hot gases generated by the incandescent coals will passa-earward to theheader, forward inthe tunnels A 25 and 27, .and upward in the chamber 32.

*the-dues 33 opened.` The fresh supply of heat is then passed upward into the reservoir 32, thisprocess being, as before stated, such'that the oven can be operated continu-4 ously without any stops whatever.

A feature of importance is the 'charging of the bread into the rotating reel at the lowest point in its travel. ln this manner, since the drum is air tight, the first steam or moisture arising from the green loaves when first coming in contact with the heat, passes upvvard'through the other trays of bread. The gases caused by the evaporation of the moisture in the dough are in this way retained entirely within the drum. rl`his is found to result in. a very superior quality of bread such as cannot be obtained when the gases are allowed to pass out of the oven, or Where lthe gases of combustion come in actual contact with the dough.

The 'drum inclosing. the reel'is spaced away from the walls of the oven. at all points so as to allow a thorough circulation of the gases, contained within the reservoir 32 entirely around the drum.

Since the shaft rotating reel extends longitudinallly through the oven, a battery of ovens may be placed side by side without providing` intervening spaces for operating mechanism, thus materially economizing in floor space.

The continuous operation .of thisy oven may be likened somewhatv to the continuous operation of a steam boiler. Hitherto ovens have been constructed and placed von the market which have been erroneously termed continuously operating` ovens. As far as understood, however, these ovens cannot in actual operation be run continuously, it being necessary in all cases to shut down at least once day for various purposes. ln our oven, however, as in the continuously operated boiler or steam generator, the fir ing is intermittent and can be continued as long as desired. I

The bottoms lei of the trays are suspended by l'nacletsand bearings lll in-the shaft 13. They are free to swing and maintain a horizontal position as the reel rotates through its circle of travel. vertically curved guide shoes la are secured oucach side of the longitudinal centers of the trays` their vertical movements.

so as toguide the' trays pastV one another as' they are lifted or lowered. This prevents any possibility of the bread pans being upn set should one of .the journals 1,4 stick slightly and prevent its trays from main.

taining an exactly horizontal position. Bythe 'use of these shoes the trays maybe made much wider than .would otherwisebe the case 'as it prevents interference between the edges as thev trays pass one'another.v HeavyV slabs of -soapstone 14 orother .goed heatlretaining material are :placed in thel bottoms ofthetiays.' j

' In Figs 7. and 8. we-have shown a modified formjof tray inwhich longitudinal rods 39 and if'transverse rods 40 rcplace'the sheet metal bottoms 14; ofthetrays ahd'serve to support. thesoapstone slabs. From actual experienc'eit hasbeen found that the bread 4has a poor quality, colorless bottom when the pans are supported upon' thin sheet metahbott'oms, jthis being due to4 the fact thatgheat radiates' less readily from thinV iron'than from a thick, heat-retainingsubstancesuch as 'soapstoneyv -On'e of the objects aimed at by the present construct-ion isl to greatly reduce the ground area requiredyfor an oven of given-capacity in comparisonwith that required for those/ bread-baking' ovens which are commonly in use-.haring long, wide flat stationary 'hearthsl By 'employing a'reelstructure of the sort indicated, large pan-carrying' trays can be s6 'arranged that at alltimes many of themare superposed in relation to. others, -andconsequently the ground area can be greatly reduced. And not only are the trays in they present. apparatus so arranged as to bein. different horizontal planes during theirvertical movements, but moreover they are'so connected together that this reducing of ground area Ais carried still further. They are supported at radial distances from the axis so short that there Woldbe danger 4of their interfering except for the provision herein made of the guiding and, bufling Adevices at 11i". These are preferably of a shape such as shown. They .can be. formed by. attaching curved strips or bars to the trays and arranged to have their convex surfaces outward. These prevent any of the projecting parts of the trays from' catching one with another andA insure that-they shall successively pass each other although brought close together in The trays may be made relatively wider and the total panv carrying area is largely increased.

' lVe are aware of the fact that rotary reel ,like carriers have been, and today are, used in thev baking of crackers and similar articles, but do not know of ovenstructures of this class beingused for the baking of bread.

W hile bread 'is'I being baked, it is well known 1that 'the'mois'tue should not be reduced in the immediate neighborhood of the dough and also that the heat should be brought to the several surfaces of the dough, entirely around the loaf, with as much uniformity and equality as possible. One of these ends is. reached by making the thin sheet. metal drum or casing as tight as possible against the passage of air, gas or, vaporv it having exterior heat chamber of the oven or with theexterior atmosphere.v The moisture and vapors that are given off during the baking process are all retained lin this tight in. closure; and to reduce the interior volume, the lower section of the shell or casing is, as above described, flattened so as to bring it as closeas possible to the paths of travel of all the points that rotate, thus insuring that the trays while moving through the lower part of their circleshall pass close to the heat-imparting'shell, at the bottom, and also, as noted, reducing the cubical volume of the interior to .such extent as to keep the moisture or water vapor immediately adja- Cent to the dough;- The second end referred to abovelis attained partly by this arrangement of the parts of the shell or casing, but

nlargely by providing as pan supports, (not the thin sheet metal which has beenheretofore used 1n cracker ovens adapted to 1m- `part a quick, dry heat and which does not possess the capability of absorbing and Ietaining a large quantity of heat and imparting it through a prolonged period of time, but) loor sections analogous to the refractory, porous, non-metallic stationary hearths which to this day are'used in the most successful bread baking ovens. These supports or tray bottoms are illustrated at 14C in the drawings. They are non-metallic and 'can be formed of any ofvseveral mate rials adapted for this purpose. Ne have found that a porous natural stone of the class of soapstone gives the best results becauseK-of its lightness and capacity to conserve heat. Each tray bottom can he built up of a number of sections of the non-metallic, porous material used, this depending upon the size. At present, with'trays from three to four feet wide and twelve to .fifteen feet long, we have found that slabs of the.

scapstoneflike ymaterial from one to two inches in thickness are the most eicient. rlhese can be supported either as shown in Fig. 6 directly upon a sheet metal carrier or brttom, or they can be carried in an open framework as shown in Figs. 7 and .8. In the latter construction the heated gases'in the interior of the casing are allowed to play directly upon the bottoms of the pbrous slabs and, at the same time, in case of fracture, the dropping of pieces is prevented.

.The vertical height of the oven is very much greater than the horizontal transverse no communication whatever eitherwith the" and heat reservoir.

Width. The oven walls being approximately twice the combined vertical heights of the lire .chamber and baking drum, there remains between the upper surface of the fire chamber and the lower surface of the baking drum a relatively high open chamber The air tight baking drum is positioned in the upper part of the chamber and slightly separated at its upper half from the insulated walls of the chamber. The proportions of the heat reservoir or chamber 32 are so great as compared with the size ofthe baking drum that a very large quantity of heat is stored and transmitted tothe drinn while .the operation of changing tire is going on. Because of this the baking temperature in the air-tight drum is retained at a constant temperature and the fire in the furnace can be attended to without disastrous effect.

What we claim is:

lsThe combination of the furnace, the imperforate heavy heat-insulating outer walls inclosing a vertically elongated hot gas space'wh ich is permanently closed against any external communication except near the bottom with the furnace, a baking container positioned within the upper part of the said hot gas space at a considerable distance from the bottom thereof and provided throughout with thin permanently7 gastight walls through which heat is lreadily transmitted to the interior from the said hot gas space, and means whereby material to be baked can be inserted into the container.

2. The combination of the furnace, the imperforate heavy heat-insulating outer walls inclosingI a vertically elongated hot gas space which is permanently closed against any external communication except -near the bottom withthe furnace, a baking container positioned entirely within the upper part of the said' hot gas space at a considerable distance from 'the bottom thereof and having throughout thin permanently gas-tight walls all of which are separated from the said insulating walls and through which heat is readily transmitted at all points from the said hot gas space to the interior of the container, and means whereby material to be baked can be inserted into the said container.

3. The combination of the furnace, the ilnperforate. heavy heat-insulating outer walls inclosing a vertically elongated hot gas space which is permanently closed against any external communication exceptnear the bottom with the furnace, a baking container positioned within the upper part of the said hot gas space at a conside `able distance from the bottom thereof and provided with thin permanently gas-tight walls through which heat is readily transmitted from the said het gas space to the interior of the container, and a relatively small airtight duct extending through one of the heateinsulating walls to the said container near the bottom thereof, whereby materialto be baked can be inserted into the container without, substantial loss of heated gases or vapors therefrom.

t. The combination of the furnace, the

extending through one of the heat-insulatfhg walls to the said container near the bottom thereof, whereby material to be baked can be inserted into the container Without substantial loss of heated gases or vapors therefrom. L

5. The combination of the furnace, the imperforate heavy heat-insulating outer walls inclosing a. verticallyA elongated hot gas space which is permanently closed against any external communication except near the bottom with the furnace, a baking container positioned Within the upper part of the said hot gas space at a considerable distance fromthe bottom thereof and pro vided with thin permanently gas-tight walls through which heat is readily transmitted to the interior from the said hot gas, space,

ka rotary pan-supporting` rcel in the said container, and means whereby material to bebaked can be inserted into the container to be carried by pans of the said reel.

G. Thecombination of' the furnace, the imperforate heavy heat-insulating outer walls inclosinga vertically elongated hot gas space which is permanently closed against anyV external communication except near the bottom with the furnace, a horizontal rotary pan-supporting rcel positioned Within the upper part of the said hot gasyspace at a considerable distance from the bottom thereof, a container vfor the reel provided with thin. permanently gas-tight walls througlr which heat is readily transmitted to the interior from the said hot gas space, the said walls of the container boing shaped and positioned to lie substantially equidistantly from all of the pans of the reel, and means whereby material to be baked can be `inserted into the container to be carried by pans of the said rcel.

7. The combination of the furnace1 the imperforate heavy heat-insulating outer walls inelosing'a vertically elongated hot gas space which is permanently closed vinterior of the container, a rotary pan-sup porting reel in the said container, and means whereby material to be baked can be inserted into the container t0 be carried by pans of the said reel. y

8. The combination of the furnace, the imperforatel heavy heat-insulating outerwalls inclosing a vertically elongated hot gas space which is permanently closed against any external communication except near the bottom with the furnace, a baking containerpositioned within the upper part of the said hot gas-space at a considerable distance from the bottom thereof and provided with thin permanently gas-tight walls through which heat is readily transmitted from the said hot gas space to the interior of the container, a rotary pan-supporting reel in the said container,4 and a relatively lsmall air-tight duct extending through one of the heatsinsulating walls to the said'con; tainer near the bottom thereof, whereby material to be baked can be inserted into the container to be carried by the pans of the reel without substantial loss of heated eases or 'vapors therefrom. i

9. The combination'of the' furnace, the imperforate heavy heat-insulating 'outer walls inclosing a vertically elongated hotv gas space which is permanently closed against any external communication except ne, r the bottom with the furnace, a damper for optionally cutting ed communication between the furnace and the hot gas space, a baking container positioned within the upper part of the said hot gas space at a considerable distance from the bottom thereof, and provided with thin permanently gastight walls through which heat is readily .transmitted to 'the interior thereof from the said hot gas space, and means whereby .material to be baked can be inserted into the container.

10. The combination of the nace to the external air, a baking container A positioned within the upper part of the said het gas space .at a considfaahe distance furnace, the imperforate heavy heat-insulating outerV from the bottom thereof, and provided with thin lpermanently gas-tight walls through which heat is readily transmitted tothe interior thereof from the -Saidliot-igas space and means whereby material to be baked can beinserted into the container.

1l. In a baking oven, 'the combination of the baking container, the main outer walls inclosing an insulated chamber in the upper part of which the said baking container vis located, the furnace positioned belowl the insulated chamber, passages at each side of the furnace, the header connecting-the passages and the furnace, the dampered smoke flue connecting the said passages with the atmosphere, and-the dampered ilues connecting the passages with the insulated chamber.

l2. In a baking oven, the combination of the main outer walls inclosing an insulated chamber, thegas tight baking container positioned in the upper portion of the chamber, the three parallel tunnels formed in the lower portion of the'oven, the ire grate located in the central tunnel, the header connecting the three tunnels at o-ne end thereof, the smoke lues connecting the opposite ends of the two outer tunnels with the atmos phere, and the dampered flues connecting the two outer tunnels with the insulated chamber.

13'. In a baking oren, the combination of the main outer walls inclosing a heat'insulated chamber, the baking container positioned in the upper portion of the said chamber, three tunnels formed in the lower portion. of the oven and insulated from the said container, theheader connecting the three tunnels at one end, the fire grate positioned in the central tunnel, the dampered smoke lues connecting the ends of the two outer tunnelsy with the atmosphere, and dampered flues connecting Vthe two ruiter tunnels with the heat insulated Chambon 14. Iii a baking oven, the combination of a rotating reel, baking trays suspended from the periphery of the reel, and a sheet metal drum having its upper portion semi-circular in cross section and its lower portion subs'tantially elliptical in cross ,section with its inner surface in close proximity to the baking trayse l5. In a bread-baking oven mechanism, the combihation of the exterior non-conducting wall inclosing a tight hot gas chamber, the rotary pan-supporting -reel positioned in the Vupper part of the said chamber, the tightly closed sheet metal drum surrounding the reel and supported within the non-conducting wall and haring an unobstructed air passage extending entirely around it.

16. In a bread-baking apparatus, the combination of a rotary pan-supporting reel, a tightly closed sheet metal-drum entirely surrounding the reel, a furnace structure having walls of noirconducting materlal eX,A

tending-from a base region up to relatively high points and having an air-tight arched roof part surrounding the top of the drum, and the ire'ehamber in the base structure of the furnace said irechamber beingconstructed and arranged substantially as set `forth to provide a 'relatively deep, Wide hotair chamber situated vertically between the fire chamber and the drum and extending continuously from one of the non-conduct` ing side vertical furnace Walls to the other and continuously from the top of the fire chamber' to the bottom of the stantially as described.

17. In a bread-baking apparatus, the conibination of the oven having non-conducting 'walls extending vertically from a base'to relatively high points and formed with an air-tight noli-conducting roof or top, a re chamber in the base of the oven cut off from communication with the interior chamber above the fire chamber, said interior chamber comprising an upper section adjacent the roof and a relatively deep section immediately above the lre chamber, an air-tight drum in said upper section adjacent the roof or cover, a rotary pan-carrying reel in the W ILLIAM S. COR-BY. JAMES L. PARSONS, Jn.

lVitnesses:

N. CURTIS LAMMOND, Grenen E. EDELIN. 

